Threading machine



Nov. 26, 1929i w. L. HWLETT 1,737,310 I I THREADING MAHINE Filed-magg, 1927 2 sheets-sheen 1 1f i` 47 Y Nov. 26, 1929. Yw. L. HowmsT-r 1,737,310

THREADING MACHINE.

Filed-May 4, 1927 2 sheets-sheet 2 Patented Nov. 26, 1929 WILLIAM L. I-IOWLETT, OF LOS ANGELE'CALIFORNIA THREADING VIACI-INE Application led May 4, 192'?.

My invention is a. threading machine particularly adapted for threading pipes or rods.

An object of my invention is the construction of a threading machine of an automatic type for threading pipes and rods, in which the work will be fed forward into the dies and when the threading action is completed the dies are automatically retracted from the work.

A more specific object of my invention is the construction of a rotary die holder having dies controlled by a cam-disc in their movement to and from the work and such die holder has a device connected therewith to release the dies at the proper time, allowing the holder to rotate around the rod or pipe without cutting same.

Another object of my invention is in the work carrier which advances the work to the tool having a tripping dog which trips the die holder to release the dies from the work.

My invention will be more readily understood from the following description and drawings, in which:

Figure 1 is a plan view of my threading machine, taken in the direction of the arrow 1 of Fig. 2. A

Figure 2 is a side elevation taken in the direction of the arrow 2 of Fig. 1. Y- V Figure 3 is a longitudinal section on the line 3 3 of Fig. 1 in the direction of the arrows, v

Figure 4 is a transverse section on the line 4 4 of Fig. 2 in the. direction of the arrows, showing the face plate of the die'holder in elevation.

Figure 5 is a view similar to Fig. 2 with the work advanced to the tool.

Figure 6 is a detail section on the line 6-6 of Fig. 4 developed.

The stationary parts of my threading machine comprise a base v11 having` slideways 12 therein, a standard 13 having a journal 14 therein, a horizontal lug 15 having a vertical journal 16 therein. The standard is formed in two parts with a diametric split 17 and having lugs v18 with clamping bolts 19 therethrough.

The die holder is constructiesV substantially as follows:

Serial No. 188,638.

A hollow shaft 20 is journaled in the standard 13 on the journal 14 and has a back plate 21 on one side. This plate is provided with transverse slideways 22 in which the dies 23 v may slide, these being insertable through lat- 55 eral openings 24 in such plate. .The dies are provided with die holders 25 secured thereto in any suitable manner, and each lug has a pin 26. The face plate 27 is of disc like construction, having a central opening 28 to accom- 60 modate the work, and on its inner face a pair of cam shaped grooves 29 to accommodate the pins 26 of the dies. The face plate also has an arcuate slot 3() with an enlarged opening 31 through the plate in the slot. Thefplate as is provided with a stopping lug 32 and is held in position on the back plate 21 by means of grooved lugs 33. The face plate is also V provided with a bracket' 34 through which is threadedthe adjusting screw 35. This ad- 7o justing screw is adapted to contact with the end surface 36 of the releasing lug 37, which is rigidly secured to the back plate 21 and extends outwardly therefrom.

The tools are driven by a large gear 38 on 75 the vertical shaft 40 may be driven by a chuck' 8o 43 connected to a drill press or the like.

The workholder, designated generally by the numeral 44, comprises a pair of vise jaws 45 which are-actuated to and from each other by a screw 46 in the ordinary manner turned 85 by a hand wheel 47, these jaws sliding inthe slideway 48 transverse to the base. A'bar 49 secured to the work holder base 50 engages the screw 46, thereby being held rigid in ref lation to the jaws, and such bar is connected by a link 51 to an operating handle 52 pivoted at 53 to the base 12. The forward end of the base 11 has adog 54 mounted thereon on a pivot pin 55, this dog being normally thrust rearwardly by a compression spring 56 which 95 is tensioned between a lower part of the dog and part of the base. The upper part of the dog has an operating end 5 7, one part of which 58 is adapted to engage the stopping lug 32 and. the forward downwardly curved part 59 loo is positioned to engage the releasing lug 37. The dog has a rearward extension 60 for manual operation if desired. The dog 54 may be pressed forward by a spring 6l in the forward movement of the work holder-base, as shown 1n Fig. 5. f

Theface plate and dies are assembled on the back plate by engaging said plate loosely in the lugs 33 with the face plate slightly tilted out at the top. The dies may then be inserted through the opening l241 in the back plate into the slideways and `the `pins engaged in the cam grooves 26. A clamping cam 62, pivotally mounted on a screw 63 which is connected vto the back plate, may then be fitted through Vthe opening 3l and such clamping cain may travel in the arcuate slot 30. A stopy screw 64 is also screwed into the back plate, this screw extending through the slot 30. y

` The manner'of operation and functioning yofiny threading machine is substantially as followsi After assembling the dies and therback andthe face plate, as lalcove described, the dies may he adjusted to the diameter of the work vby positioning a rod or a bar to be threaded inthe work holder, gripping this in the device 45 and moving the work holder forwardby operation of the lever 52. The face platel is then rotated, causing thev cam grooves'26 to act on the dies 23 throilgh the inediiim ofthe ins 26 and the die holders 2,5. When the ies are-'properly adjusted for the proper diameter of cutting, the clamping cam 62 is pivoted on the pin 63 to eirert a pressure against the face plate, thus :holding it rigidly clamped in relation to the back plate. The screw7 7Gil is then inserted in the back platethrough the slot 30 and acts as a stop, limiting the movement in one direction; The adjusting screw is adjusted to engage the end 36 of the releasing lng Y 2 to that shown in 5; A f rotation of the todl holder engages 'first the.

and form a stop in the other direction of the movement. l

Then the Clutch is thrown in, the die tools are rotated, and when the threading is started the. work isdrawn forward automatically and is not necessary for an operator to manipulate the hand lever 52; 'In this drawing forward of the work holder, the spring (il engages the back of 'the dog 54 and tilts 'such rdog from the position .shown in Fig. This dog in the pressing cam 62andtrips such cam, the earn engaging the'p'art 58 of the dog. This part 58 next engages the stopping lug 32 which rotates the face plate relatively to the backing plate and in so doing causes the cam grooves 26 to act on the dies, ret-ractin'g such dies radially outwardly from the work. These stop lugs and the face plate are forced in arelative rotation hackwardly on the back plate until the releasing lug 37 engages the downwardly turned part 59 of the dog 54, and presses this dog rearwardly against the pressure of the spring` 61, thus permitting the continued rot-ation of the tool holder with the tools retracted from the work. Thus the tool holder may continue rotating without any further action on the work and theclutch maybe vreleased at a convenient time. As the lug 3d and stop screw 35 are positioned to engage the releasing 37, these also thrustthe dog backwardly against the tension ofthe spring'l on each rotation.

It will thus be seen that I have developed a simple 'construction of threading machine having the dies fed inwardly and outwardly a eain type of action on a farce plate, the face plate heilig clamped to a rotating back plate `and rotating therewith, holding the ,dies in adjusted position, also that the work after being Astarted is fed forwardly automatically by the dies and after a predetermined amount of threading has been done, the dies are automatically retracted from the work, allowing the die holderand the dies to continue their rotation until the power transinisison is shut off. y

A feature of my threading `machine is that it may be mounted on the table of a drill press or the like and the chuck 43 engaged in the drive spindle of such press, thereby transmitting power to the threading dies. The threading machine thus forms a simple Iequipment which may be `nro'un'ted onthe drill press table or removed therefrom'as required;

, 'Various changes'may loemade- `in the principl'es of my invention without departing from the Sprit theretf, as ser for-th in the description, drawings and claims.

I claim:

1. A lthreadingmachine eomprising in rcombination a hollow rotatable shaft, a back plate mounted on said shaft, means forming a `support and ijournal for -said shaft, dies slidable inwardly and outwardly on the back plate, a face plate mounted on th'e'back plate and having cam means interengaging `with the dies to shift the dies, said face plate having' an arcuate slot, a clamping device attached to 'the back plate-extending through said slot to clamp the face plate to the back plate, a stop lug on the face plate, a slidable work holder, means actuated by the movement of the work holder towards theV face platev to engage the clamping device and release same to Vun'cl'amp the face plate, said means engaging the stop lug and shifting the face plate relative to the back plate, and

means on the back plate to allow rotational versely movable therein, a face plate mounted on the back plate, interengaging means be tween the face plate and the dies to shift said dies transversely, a face plate having an arcuate slot, a clamping device attached to the back plate extending through said slot to clamp the face plate to the back plate, a stop lug on the face plate, a releasing lug on the back plate, a Work holder slidable in relation to the face plate, means actuated by the work holder in its movement towards the face plate to engage the clamping device and release same, secondly to engage the stop lug and rotate the face plate relative to the back plate to retract the dies, said means being engaged by the releasing lug to prevent said means engaging the stop lug.

3. A threading` machine, as claimed in claim 2, the means actuated by the work holder comprising a pivotally mounted dog, having one part positioned to engage the stop lug and another part positioned to engage the releasing lug.

4. A. threading machine comprising in combination a rotary lhollow shaft suitably mounted and journaled, a back plate thereon, having dies transversely movable, a face plate having interengaging means with the dies to shift same, said face plate having an arcuate slot with an enlarged opening, a clamping cam mounted on a pin secured to the back plate extending through said slot', the cam pressing the face plate to clamp same to the back plate, a stop lug mounted on the face plate, a releasing lug on the back plate, a pivotally mounted dog secured adjacent the face plate, a work holder slidably mounted, means actuated by the movement of the Work holder to shift the dog, said dog first releasing the clamping cam t0 release the face plate from the back plate, secondly engaging .the stop lug to rotate the face plate relative to the back plate to retract the dies, and thirdly said deg being engaged by the releasing lug to shift said dog out of the path of the stop lug.

5. A threading machine, as claimed in claim 4, and a bracket secured to the face plate having an adjusting screw, said screw engaging the releasing lug to allow adjustment of the dies.

G. A threading machine, as claimed in claim 4, a bracket secured to the face plate having an adjustinoscrew, said screw engaging the releasing dug to allow adjustment of the dies, and a stop screw secured to the.

back plate extending through the slot.

7. In a threading machine a hollow rotatable shaft suitably mounted, having a back plate thereon, with dies transversely movable thereon, a face plate having an arcuate slot,

a clamping cam pivotally mounted on a pin secured to the ack plate and extending through said slot, said clamping cam clamping the face plate to the back plate, a slidable work holder, means actuated by the work holder in its movement towards the face plate 

